Preparation of tetramethylethylenediamine
CA 2297127 A1 · Owner: Bulka, Robert J. · Inventors: O'Neill, Gerald J.; Bulka, Robert J.; Levesque, Albert H.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Process for the production of TEMDA in high yield by reducing 2,3-dimethyl-2,3dinitrobutane with hydrogen in the presence of a chromium promoted Raney cobalt catalyst. A solution of 2,3-dimethyl-2,3-dinitrobutane in a suitable solvent is fed to a reactor while avoiding the accumulation of 2,3-dimethyl- 2,3-dinitrobutane in the reaction medium such as by feeding it at a rate no , greater than its rate of reaction with hydrogen. In a preferred embodiment the resulting TMEDA is recovered by converting it to an amine salt by sparging carbon dioxide through the solution.
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed July 7, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended July 7, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 7, 2020.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.